Hour meters of various types are commercially available both as an add on device to a combustion engine or supplied as part of a vehicle that has a combustion engine. The hour meter provides information about the amount of time the engine has been operating. This information is useful for scheduling maintenance necessary at predetermined engine run times. In addition, hour meters may be used on test vehicles to calculate the durability of engine components as a function of engine run time.
Some existing hour meters display a service reminder icon at the end of predetermined intervals, such as scheduled maintenance intervals. In some hour meters, the display can be reset to remove the service reminder icon by the operator after service is performed. In other hour meters, the display resets after a predetermined period of time elapses.
One problem with the service reminder provided by current hour meters is that the service reminder icon does not provide the operator with an indication of how much time is left until service, since the service reminder icon is not displayed until service is due. In addition, if service is performed before the service reminder icon is displayed, the service reminder icon will be displayed shortly after service is performed. This could lead to confusion and could possibly cause the vehicle to be unnecessarily serviced.
There is a need for an hour meter that graphically displays the amount of time left until service is due. Such an hour meter allows the operator to see at a glance how much time is left until the next scheduled service.